mirror of
https://github.com/ceph/ceph-csi.git
synced 2024-12-18 19:10:21 +00:00
43 lines
1.4 KiB
Markdown
43 lines
1.4 KiB
Markdown
|
## pwalk: parallel implementation of filepath.Walk
|
||
|
|
|
||
|
|
This is a wrapper for [filepath.Walk](https://pkg.go.dev/path/filepath?tab=doc#Walk)
|
||
|
|
which may speed it up by calling multiple callback functions (WalkFunc) in parallel,
|
||
|
|
utilizing goroutines.
|
||
|
|
|
||
|
|
By default, it utilizes 2\*runtime.NumCPU() goroutines for callbacks.
|
||
|
|
This can be changed by using WalkN function which has the additional
|
||
|
|
parameter, specifying the number of goroutines (concurrency).
|
||
|
|
|
||
|
|
### Caveats
|
||
|
|
|
||
|
|
Please note the following limitations of this code:
|
||
|
|
|
||
|
|
* Unlike filepath.Walk, the order of calls is non-deterministic;
|
||
|
|
|
||
|
|
* Only primitive error handling is supported:
|
||
|
|
|
||
|
|
* filepath.SkipDir is not supported;
|
||
|
|
|
||
|
|
* no errors are ever passed to WalkFunc;
|
||
|
|
|
||
|
|
* once any error is returned from any WalkFunc instance, no more new calls
|
||
|
|
to WalkFunc are made, and the error is returned to the caller of Walk;
|
||
|
|
|
||
|
|
* if more than one walkFunc instance will return an error, only one
|
||
|
|
of such errors will be propagated and returned by Walk, others
|
||
|
|
will be silently discarded.
|
||
|
|
|
||
|
|
### Documentation
|
||
|
|
|
||
|
|
For the official documentation, see
|
||
|
|
https://pkg.go.dev/github.com/opencontainers/selinux/pkg/pwalk?tab=doc
|
||
|
|
|
||
|
|
### Benchmarks
|
||
|
|
|
||
|
|
For a WalkFunc that consists solely of the return statement, this
|
||
|
|
implementation is about 10% slower than the standard library's
|
||
|
|
filepath.Walk.
|
||
|
|
|
||
|
|
Otherwise (if a WalkFunc is doing something) this is usually faster,
|
||
|
|
except when the WalkN(..., 1) is used.
|